<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" 
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> 

<html xmlns="http://www.w3.org/1999/xhtml"> 
<head> 
<title>[ #443362 ] null-pointer except. for doctype in pre</title> 
</head> 

<body> 
<h1>Unofficial W3C Validator FAQ</h1> 
<p>This is a list of frequently asked questions and answers asked on the 
<a href="http://lists.w3.org/Archive/Public/www-validator-css/" 
title="Mailing list archive">www-validator-css@w3.org mailing list</a>. 

<h2>
What does "<code>org.xml.sax.SAXException: 
Please, fix your system identifier (URI) in the DOCTYPE rule.</code>" mean?
</h2> 

<p>Your XHTML document contains a document type 
declaration but the system identifier points at some 
non-W3C URI. Your document probably contains something 
like this:
</p> 
<pre> 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" 
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> 

</pre> 
</body> 
</html>